Answer:
± 
, 
Step-by-step explanation:
See the attached image
This problem involves Newton's 2nd Law which is: ∑F = ma, we have that the acting forces on the mass-spring system are: 
that correspond to the force of resistance on the mass by the action of the spring and 
that is an external force with unknown direction (that does not specify in the enounce).
For determinate we can use Hooke's Law given by the formula 
where 
correspond to the elastic constant of the spring and 
correspond to the relative displacement of the mass-spring system with respect of his rest state.
We know from the problem that an 15 Kg mass stretches the spring 1/3 m so we apply Hooke's law and obtain that...
Now we apply Newton's 2nd Law and obtaint that...
± = 
Finally... ±
We know from the problem that there's not initial displacement and initial velocity, so... and
Finally the Initial Value Problem that models the situation describe by the problem is
Well maybe he like the number 23 which is the answer
Because the shape is not undergoing a dilation, the perimeter of the original image and the new image is the same. The only thing that is changing is the placement of the original figure.
I hope this helps! :)
